/*
 * Copyright (C) 2012-2016 Facebook, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.facebook.nifty.core;

import org.jboss.netty.channel.ChannelEvent;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.SimpleChannelDownstreamHandler;

/**
 * Dispatches downstream messages from the worker threads to the IO threads,
 * so that code in IO threads do not have to worry about downstream paths
 * being invoked from multiple threads.
 */
public class NiftyIODispatcher extends SimpleChannelDownstreamHandler {

    @Override
    public void handleDownstream(ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
        ctx.getPipeline().execute(new Runnable() {
            @Override
            public void run() {
                try {
                    NiftyIODispatcher.super.handleDownstream(ctx, e);
                }
                catch (Exception ex) {
                    Channels.fireExceptionCaught(ctx.getChannel(), ex);
                }
            }
        });
    }
}
